Academic literature on the topic 'Crushing work'
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Journal articles on the topic "Crushing work"
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Mazur, Marcin. "Determination of crushing energy during vibratory crushing." New Trends in Production Engineering 2, no. 1 (October 1, 2019): 287–94. http://dx.doi.org/10.2478/ntpe-2019-0030.
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Abstract The paper presents a new method of determining the energy consumption for vibratory crushing. Using the laboratory vibratory jaw crusher with kinematic actuation of the jaws, the study of determining power consumption while crushing limestone and diabase was conducted. During the study, electrical energy used on the crushing process was measured as a function of changing design and kinematic parameters of the vibratory crusher, i.e.: jaws stroke, the outlet gap size and frequency of jaws vibration. The article presents program of the research, the laboratory test stand of the vibratory jaw crusher KW 40/1 and the test results. Comparing the theoretical crushing energy requirements, determined by the Bond hypothesis, with the values measured during tests a large differences were observed. Using the Bond hypothesis the Vibratory Work Indexes were determined for the tested materials. Their values are higher than limestone and diabase Work Indexes available in the known literatures. The explanation may be greater amount of energy transferred to the material during vibratory crushing, which results in much higher efficiency of the crushing process.
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Otahanov, Bakhrom Sadirdinovich, Nasimjon Abdulhakimovich Abdumannopov, Jamshidbek Abduzhabbor ugli Juraev, and Kakhramonjon Akramzhon ugli Giyosov. "Work on crushing soil cobles and lumber." Interactive science, no. 2 (36) (February 22, 2019): 43–45. http://dx.doi.org/10.21661/r-475586.
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The article discusses the issue of the destructibility of soil lumps and lumps depending on the processing speed and the definition of rational values, proposed a method for evaluating the working bodies in terms of the energy intensity of the process.
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Kica, Joanna, and Kenneth D. Rosenman. "Multi-source surveillance for work-related crushing injuries." American Journal of Industrial Medicine 61, no. 2 (December 4, 2017): 148–56. http://dx.doi.org/10.1002/ajim.22800.
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Ciężkowski, Paweł, Jan Maciejewski, Sebastian Bąk, and Arkadiusz Kwaśniewski. "Application of The New Shape Crushing Plate in Machine Crushing Processes." Studia Geotechnica et Mechanica 42, no. 1 (March 19, 2020): 83–96. http://dx.doi.org/10.2478/sgem-2019-0029.
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AbstractThe results of studies of the crushing process in a double toggle jaw crusher are presented. This process was carried out on six sets of crushing plates. The first three of them are used in industrial crushers – plates with a flat working surface and a triangular profile (in this work, under consideration were profiles with teeth angle γ = 90°). The fourth and fifth type refer to plates with a variable pitch t and teeth height with a triangular shape of the teeth. In the sixth solution, plates with variable pitch and width of the wedged teeth are proposed.The results of the basic process parameters are shown, that is, average degree of fineness n, technical performance Wt, crushing energy L and crushing force F, sieve analysis of crushing product. The obtained results are the basis for the assessment of the suitability of various types of plates, especially plates with a new profile, which have an altered shape in comparison with the plates used in crushers so far.The crushing tests were carried out with the same dimension of outlet slot er = 24 mm, close to the pitch size for plates with triangular profile. Tests were performed on the “Mucharz” sandstone. Samples from a series of blocks of different size and geometric shape were prepared. This work also presents feed mass influence on crushing process efficiency.The plates with variable pitch and width of teeth are beneficial because of lower crushing force and energy.
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Sakharov, D. F., and А. V. Vitushkin. "POWER ANALYSIS OF THE CRUSHING PROCESS IN A CONE CRUSHER." Izvestiya Visshikh Uchebnykh Zavedenii. Chernaya Metallurgiya = Izvestiya. Ferrous Metallurgy 61, no. 12 (January 16, 2019): 980–86. http://dx.doi.org/10.17073/0368-0797-2018-12-980-986.
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The literature devoted to cone crushers design and research of its crushing process is generally based on empirical observations, therefore it is commonly considered that material is crushed under the influence of squeezing forces exclusively. Above mentioned liter ature, in turn, theoretical base forms for crushing units design. Based on common understanding, variety of designs of cone crushing machines existing today is characterized by integrity of principles of their work. Majority of theoretical works devoted to cone crushers are focused on such characteristics as efficiency, extent of crushing, increase in percent of useful fraction in ultimate product, or on operational parameters of separate structural elements such as lining armor resistance, increase in endurance of supporting and power nodes, etc. To increase those characteristics crushing cameras with irregular shape of lining armor are designed, design of an active crushing member combines elements of active members of other crushing machines (roll, cheek crushers). However effectiveness of kinematics of active member movement is considered only from the point of view of squeezing forces generation in crushed material and minimization of its slide against it. The uppermost ener gy brought to any crushing machines is spent on loa ding destroying crushed material. Authors of this article consider that under particular circumstances such work conditions can be provided in cone crushers under which energy efficiency of materials crushing process will increase considerably. One of such conditions is creation of multi-axial stress in crushed material. Some reference designs of cone crushers are considered in the article as well as range of their app lication. Mechanism of multi-axial stress generation in crushed material promoting decrease in energy consumption of crashing process is described. Recommendations on development of operating conditions of crushing machine creating multi-axial stress in crushed material are provided.
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Nezere, Norhafizan, and Al Emran Ismail. "Crushing Behaviour of Empty Steel Tubes under Oblique Loading." Advanced Materials Research 1087 (February 2015): 11–15. http://dx.doi.org/10.4028/www.scientific.net/amr.1087.11.
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<span><p><span lang="EN-GB">This paper presents numerically the empty tube response subjected to oblique loading. According to literature survey, there have large number of works discuss on the crushing performance when subjected to axial loading. However, lack of work available on the crushing behaviour under oblique loading.</span><span lang="EN-GB"> </span><span lang="EN-GB">Therefore, this work presents the numerical studies on the crushing behavior of empty tube subjected to oblique loading. ANSYS Finite element program was used to model and solve the problem. The developed model was firstly validated with the previous result and it is found that the results obtained were acceptable. There were two important parameters were used such as tube geometry and oblique loading. According to the present results, when oblique angles were increased, the crushing performance decreased. However, when the elliptical ratios were increased, the energy capabilities increased. </span></p>
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B, Ganbat, Mungun J, Zol-Erdene D, and Davaadorj D. "The results of the study for operating regime effect of the machine tractor assembly to the quality of soil cultivation." Mongolian Journal of Agricultural Sciences 26, no. 01 (April 30, 2019): 146–51. http://dx.doi.org/10.5564/mjas.v26i01.1210.
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Due to identify the impact of work speed of CPA-3,8a cultivator in soil crushing and remove weed control, so that completed the experience on field, the soil crushing rate and working speed are identified. By using statistic analyzing methods, to indicate the correlation between data and indicators, it is given the cultivation to the quality of work. For the soil crushing rate and work speed was impacted directly, and once examine with students criteria, those had direct and linear correlation. The mathematical correlation between cultivation work speed and soil crushing rate says to identify that work speed and soil crushing rate are have suitable ratio. When working with this good working regime, the soil is well soil crushing, which is one of the opportunities to grow favorable conditions for crop cultivation.
Хөрс сийрүүлэлтийн чанарт угсрааны ажлын горим нөлөөлөх байдлыг судалсан үр дүн (кубота м 9000+кпэ-3.8а угсраа дээр)
Хураангуй: КПЭ-3.8А сийрүүлүүрийн хөрсийг буталж сийрүүлэх, хог ургамал устгах байдалд угсрааны ажлын хурны үзүүлэх нөлөөг судлaх зорилгоор талбайн туршилт тавьж хөрсний бутралтын зэргийг угсрааны ажлын хурдаас хамааруулж тодорхойлсон. Статистик шинжилгээний арга зүй ашиглан тоон үзүүлэлтүүдийн хоорондох хамаарлыг тогтоож, сийрүүлэх ажлын чанарт үнэлгээ өгөв. Хөрсний бутралтын зэрэгт, ажлын хурд хүчтэй нөлөө үзүүлж байсан бөгөөд Стьюдентийн шинжүүрээр шалгахад тэдгээр нь шууд, шугаман хамааралтай байна. Угсрааны ажлын хурд, хөрсний бутралтын зэргийн хоорондох математик хамаарал, загвараас харахад хурд, бутралтын зэргийн зохистой харьцаа тодорхойлогдож байна. Ажлын горимын оновчтой үзүүлэлтийг баримтлан угсрааг ажиллуулбал хөрс сайн бутарч үйрэх бөгөөд энэ нь таримлын ургах таатай нөхцөл бүрдүүлэх юм.
Түлхүүр үг: Сийрүүлүүр, бутралтын зэрэг, туршилт, ажлын хурд, корреляц, регресс, загвар
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Chakule, Rahul, Supriya Patil, and Poonam Talmale. "Design and Development of Can Crushing Machine." Asian Journal of Engineering and Applied Technology 9, no. 1 (May 5, 2020): 25–28. http://dx.doi.org/10.51983/ajeat-2020.9.1.1082.
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A can crusher machine is used to crush the cans for storing in bin efficiently. The crushing of cans plays a significant role in economy and ultimately helps to society. The process of cans crushing is also human and environment friendly. From literature studies it was learnt that the existing cans crushing machines are automated and can overcome the limitation of manually crushing but cost of automated cans crushing machine is high. In present study, the can crusher machine is developed economically which is automatic and eco-environment friendly. The experiments were conducted for finding the optimal pressure and force values required for effectively crushing the cans. This work helps to increase the storing capacity of cans for user. Thus, transportation cost reduces significantly due to process improvement efficiency.
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Ciężkowski, Paweł, Jan Maciejewski, and Sebastian Bąk. "Analysis of Energy Consumption of Crushing Processes – Comparison of One-Stage and Two-Stage Processes." Studia Geotechnica et Mechanica 39, no. 2 (June 27, 2017): 17–24. http://dx.doi.org/10.1515/sgem-2017-0012.
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Abstract This paper presents experimental comparison of two machine crushing technologies: one-stage and two-stage. The study was carried on a model double-toggle jaw crusher which allows crushing forces, energy and toggle displacement to be measured. The main aim of the work was to determine the energy consumption of crushing process assuming a given level of fragmentation. Studies were performed on three rocks: granite “Strzegom”, limestone “Morawica” and sandstone “Mucharz”. The material tested had a cubic shape and average dimension of 90 mm. One-stage crushing was carried out for outlet slot er = 11 mm, and two-stage crushing for er = 24 mm and 11 mm. In the tests special design of variable profile moving jaw was used and fixed jaw was flat. The analysis of the results shows that taking into account energy consumption, it is better to use two-stage crushing process. For given materials energy consumption in the two-stage crushing process was reduced by 30%.
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Ismail, Mohd Azizan, and Al Emran Ismail. "Crushing Behaviour of Empty Steel Tubes under Eccentric Loading." Advanced Materials Research 1087 (February 2015): 16–19. http://dx.doi.org/10.4028/www.scientific.net/amr.1087.16.
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This present paper describes numerically the tube responses subjected to eccentric loading using ANSYS finite element program. According to literature review, tremendous amount of works available on discussing the axial crushing of empty tube under axial loading. However, lack of work related with the crashworthiness aspect of tube crushing under eccentric loading was identified. Therefore, the eccentric compressive loading on the empty tubes were focused. There have important parameters were studied such as the eccentric loading. According to the present result, the behaviour of crashworthiness expected to increase when the increment of eccentric loading was introduced. The crashworthiness behaviour and energy absorption capabilities demonstrated efficiently by the collected data mean crushing force and peak crashing force.
Dissertations / Theses on the topic "Crushing work"
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Huňka, Jan. "Stavěcí mechanismus štěrbiny kuželového drtiče." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232135.
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This master’s thesis deals with the obtuse-angled cone crushers especially about design of the individual parts of the adjustment mechanism. Most space is devoted to functional calculation and subsequent technical construction of the new design of obtuse-angled crusher where the output setting is adjusted using the motion thread and hydraulic locking system for compensating the thread clearance. The parameters are chosen with regard to the already established older types of cone crushers produced by PSP Engineering, a.s. An inseparable part is the calculation verifying the functionality of the motion thread and gearing. Another essential part of this work are stress analysis of the slot adjusting mechanism design using finite element method and considering two states - adjusting of the slot and crushing itself.
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Knudsen, Donald L. "A Crushing Truth for Art: Martin Heidegger's Meditation on Truth and the Work of Art in Der Ursprung des Kunstwerkes." Thesis, 1987. http://hdl.handle.net/10756/291042.
Full textBooks on the topic "Crushing work"
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Phillips, Dwayne. Working up to project management: How crushing rocks at the asphalt plant prepared me for government work. New York: Dorset House Pub., 2008.
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Phillips, Dwayne. Working up to project management: How crushing rocks at the asphalt plant prepared me for government work. New York: Dorset House Pub., 2008.
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Knudsen, Donald L. A crushing truth for art: Martin Heidegger's meditation on truth and the work of art in Der Ursprung des Kunstwerkes. Toronto: Institute for Christian Studies, 1988.
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Phillips, Dwayne. Working Up to Project Management: How Crushing Rocks at the Asphalt Plant Prepared Me for Government Work. Dorset House, 2008.
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Charles, J. E. Crushing the Works of Witchcraft. CreateSpace Independent Publishing Platform, 2018.
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Zola, Émile. La Débâcle. Edited by Robert Lethbridge. Translated by Elinor Dorday. Oxford University Press, 2017. http://dx.doi.org/10.1093/owc/9780198801894.001.0001.
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‘My title speaks not merely of war, but also of the crumbling of a regime and the end of a world.’ The penultimate novel of the Rougon-Macquart cycle, La Débâcle (1892) takes as its subject the dramatic events of the Franco-Prussian War and the Commune of 1870-1. During Zola's lifetime it was the bestselling of all his novels, praised by contemporaries for its epic sweep as well as for its attention to historical detail. La Débâcle seeks to explain why the Second Empire ended in a crushing military defeat and revolutionary violence. It focuses on ordinary soldiers, showing their bravery and suffering in the midst of circumstances they cannot control, and includes some of the most powerful descriptions Zola ever wrote. Zola skilfully integrates his narrative of events and the fictional lives of his characters to provide the finest account of this tragic chapter in the history of France. Often compared to War and Peace, La Débâcle has been described as a ‘seminal’ work for all modern depictions of war.
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Balay, Anne. Semi Queer. University of North Carolina Press, 2018. http://dx.doi.org/10.5149/northcarolina/9781469647098.001.0001.
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Long-haul trucking is linked to almost every industry in America, yet somehow the working-class drivers behind big rigs remain largely hidden from public view. Gritty, inspiring, and often devastating oral histories of gay, transsexual, and minority truck drivers allow award-winning author Anne Balay to shed new light on the harsh realities of truckers' lives behind the wheel. A licensed commercial truck driver herself, Balay discovers that, for people routinely subjected to prejudice, hatred, and violence in their hometowns and in the job market, trucking can provide an opportunity for safety, welcome isolation, and a chance to be themselves--even as the low-wage work is fraught with tightening regulations, constant surveillance, danger, and exploitation. The narratives of minority and queer truckers underscore the working-class struggle to earn a living while preserving one's safety, dignity, and selfhood. Through the voices of drivers from marginalized communities who spend eleven- to fourteen-hour days hauling America's commodities in treacherous weather and across mountain passes, Semi Queer reveals the stark differences between the trucking industry's crushing labor practices and the perseverance of its most at-risk workers.
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Take Up The Sword Of The Spirit: Crushing Curses With The Word Of God. Creation House, 2003.
Find full textBook chapters on the topic "Crushing work"
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Lee, Jung-Woo, Hyo-Gon Kim, Jung-Woo Park, Young-Ho Choi, and Jin-Ho Suh. "Measuring Work Efficiency of the Rock-Crushing Operation of the Hydraulic System." In AETA 2016: Recent Advances in Electrical Engineering and Related Sciences, 723–28. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-50904-4_73.
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Toaff, Ariel. "Converts and Apostates." In Love, Work and Death, 143–65. Liverpool University Press, 1996. http://dx.doi.org/10.3828/liverpool/9781874774198.003.0008.
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This chapter studies the phenomenon of conversion and baptism in the Italian cities of the late Middle Ages, assessing its impact on the Jewish community. The Jews of late medieval Italy were dispersed throughout hundreds of small and isolated communities, immersed in a Christian society whose power of attraction could make itself felt well in excess of an already crushing numerical superiority; this inevitably left their numbers exposed to depletion by conversion and baptism. Scholars are virtually unanimous in agreeing that the number of baptisms within Italian Jewry rose sharply during the Counter-Reformation, as a result of the Church's increasingly intense policy of conversion and the antisemitic measures taken by the popes from the middle of the sixteenth century onwards. One constant policy among the Umbrian communes towards converted Jews was to water the new plants with more or less abundant alms and other benefits, such as exemption from taxes and the right of citizenship. However, whatever the reasons for their conversion, neophytes often became objects of hostility in Jewish circles, while at the same time finding themselves exposed to the distrust and suspicion of Christian society.
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Lynch, Michael E. "Tragedy and Redemption." In Edward M. Almond and the US Army, 134–56. University Press of Kentucky, 2019. http://dx.doi.org/10.5810/kentucky/9780813177984.003.0009.
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With Marshall’s permission, Almond reorganized the 92nd Infantry Division, keeping all the “best” soldiers in one regiment, while farming out the other three regiments for training and other duties. Almond gained a white infantry and the 442nd Infantry (Nisei) Regiment, whose combat performance was already legendary. This made the 92nd Infantry Division the most racially integrated division in the Army, and it acquitted itself well. The elation Almond felt at finally seeing his unit succeed, however, could not assuage a crushing sadness: his son was killed in combat. His letters home to Margaret reveal a father’s anguish, his seething anger, and his love for and devotion to his only grandson, and his steadfast intent to carry on with the mission. Almond’s tremendous work ethic and dynamic personality helped him push past his personal grief and focus on his mission.
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Smith, Steven C. "Battles Won and Lost." In Music by Max Steiner, 183–200. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190623272.003.0013.
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This chapter begins with a concise history of Warner Bros.—its inception, its combative founders, and the key role that music played in the studio’s releases. Steiner’s first work at Warners, The Charge of the Light Brigade, would be another milestone—a grand action-adventure score foreshadowing contemporary film music. Despite a tight deadline, and high expectations from producer Hal Wallis, Steiner triumphed, which made his return to Selznick all the more crushing. David’s increasing micromanagement extended to music; and Max was devastated when the producer who had called himself Steiner’s “biggest fan” eviscerated his score for A Star Is Born, Selznick’s latest film. A proud (if often insecure) individual, Steiner resigned his post at Selznick but stressed to the producer his desire to remain friends. His motives were not solely personal. Max knew that Selznick was about to film the most successful novel of the decade: Gone with the Wind.
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Layman, Daniel. "Hodgskin’s Libertarian Groundwork." In Locke Among the Radicals, 67–98. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190939076.003.0003.
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Thomas Hodgskin, an Englishman who wrote widely in political economy during the first half of the nineteenth century, professed almost slavish devotion to Locke. In following in what he took to be Locke’s footsteps, he devoted his scholarly life to a polemic against “idle” capitalists and landowners. But he simultaneously defended an unflinchingly individualist interpretation of the Lockean project. According to Hodgskin, the world is common only in the sense of being originally unowned, and everyone has a right to anything he can create by laboring on it. He argues that the crushing inequality he observed around him in the fields and cities of the industrial revolution was attributable solely to the violence and cupidity of governments and their cronies. In working out this theory, Hodgskin sketched the principle features of a distinctly libertarian resolution of Locke’s property problem. According to this resolution, there is no problem about reconciling the common right to the world with the growth of private property because the common right is simply a liberty for each person to make use of the world as he might see fit. Thus, despite his left-leaning criticisms of capitalism and absentee landownership, Hodgskin planted seeds that would develop, in Spooner’s later work, into the core of the right-libertarianism we know today.
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Gross, Alan G. "Rachel Carson: The Ethical Sublime." In The Scientific Sublime. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190637774.003.0012.
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Rachel Carson has become Saint Rachel, canonized time and again by the environmental movement. May 27, 2007, marked the 100th anniversary of her birth. In that year, the Cape Cod Museum of Natural History in Brewster, Massachusetts, hosted a major Rachel Carson centennial exhibition. The show was a partnership project of the museum and the US Fish and Wildlife Service, and it featured artifacts, writings, photographs, and artwork from Carson’s life and career. In 2012, the 50th anniversary of the publication of Silent Spring was commemorated by a Coastal Maine Botanical Gardens event and exhibit. From September 7 through October 23, the exhibit presented artwork, photos, and interpretive panels in the visitor center. Canonization, and the posthumous fame it bestows, comes at a price: the disappearance of the Rachel Carson whose work was driven by two forces. The first was the love of nature. A perceptive review of The Sea Around Us compares Carson with great science writers who share with her a love of nature: . . . It is not an accident of history that Gilbert White and Charles Darwin described flora and fauna with genius, nor that the great mariners and voyagers in distant lands can re-create their experiences as part of our own. They wrote as they saw and their honest, questing eye, their care for detail is raised to the power of art by a deep-felt love of nature, and respect for all things that live and move and have their being. . . . The second force was the love of a woman, Dorothy Freeman, a person who in Carson’s view made her later life endurable and her later work possible: . . . All I am certain of is this: that it is quite necessary for me to know that there is someone who is deeply devoted to me as a person, and who also has the capacity and the depth of understanding to share, vicariously, the sometimes crushing burden of creative effort, recognizing the heartache, the great weariness of mind and body, the occasional black despair it may involve—someone who cherishes me and what I am trying to create, as well. . . .
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Dalton, David R. "General Comments." In The Chemistry of Wine. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190687199.003.0026.
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Viticulture, it will be recalled, is the art and science of vine-growing and grape-harvesting, and it was the subject of Sections I–IV (Chapters 1–14). Enology, the subject of this Section (Chapters 15– 20), is the art and science of winemaking. Much of what follows in this brief Chapter on General Comments is expanded upon in other Chapters in this Section. In making the wine, it appears to be generally agreed that where possible it is best to follow the traditional methods to produce the best results. However, it should be clearly understood that work is underway to engineer yeast to make it more alcohol tolerant and to use the yeast to produce specific compounds recognized as being particularly flavorful. Additionally, as the number of vintners has grown, finding the proper oak for casks is becoming ever harder. Therefore, the art of reworking old oak casks or even avoiding them altogether (e.g., by aging wine in the presence of oak chips) may be used. In the same vein, it is widely recognized that stoppers other than cork may be used, so that the day may come when the cork stopper will be a thing of the past. Traditionally, grapes are taken directly from the vineyard to be crushed, and it is still the case in many of the oldest and most respected vineyards that this practice will continue. However, as the use of pesticides and fungicides has increased, methods for rapid washing and then drying of grapes before crushing may be employed. The arguments against these extra steps are mainly two. First, lingering water would dilute the grape juice. Second, the adventitious yeasts that might be removed by washing or deactivated by drying are often desired for the production of the vintage. Indeed, it has been argued that unique fungi, which might be exclusive to the most prestigious vineyards, are important to the production of the best wines. The issue of washing versus not washing has been investigated, and it was concluded for the case examined that only minor changes are effected by washing.
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McElroy, Michael B. "Hydro: Power From Running Water." In Energy and Climate. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780190490331.003.0016.
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As discussed in Chapter 4 and illustrated in Figure 4.1, close to 50% of the solar energy intercepted by the Earth is absorbed at the surface. Approximately half of this energy, 78 W m– 2, is used to evaporate water, mainly from the ocean. What this means is that evaporation of water accounts for as much as a third of the total solar energy absorbed by the Earth (atmosphere plus surface). The atmosphere has a limited ability to retain this water. Evaporation is balanced in close to real time by precipitation. A portion of this precipitation reaches the surface in regions elevated with respect to sea level— in mountainous locations, for example. It is endowed in this case with what we refer to as potential energy (Chapter 4). This potential energy can be stored (in lakes or dams, for instance), or it can be released, converted to kinetic energy (directed motion) as the water flows downhill on its return to the ocean. And along the way, energy can be captured and channeled to perform useful work. An early application involved exploiting the power of running water to turn a flat stone, one of two that constituted the apparatus used to grind grain, the other remaining stationary during the grinding process. The Domesday Book records that by AD 1086 as many as 5,624 water mills were operational in England south of the River Trent, deployed not just to grind grain but for a multitude of other tasks, including, but not confined to, sawing wood, crushing ore, and pumping the bellows of industrial furnaces (Derry and Williams 1960). Later, running water would provide the motive force for the textile industry that marked the beginning of the industrial age in North America, specifically in New England (Steinberg 1991; McElroy 2010). The most important contemporary application of water power involves the generation of electricity, the bulk of which is obtained by tapping the potential energy stored in high- altitude dams, a lesser fraction from the kinetic energy supplied by free- flowing streams (what is referred to as run- of- the- river sources).
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Musser, Amber Jamilla. "Femme Aggression and the Value of Labor." In Sensual Excess, 144–66. NYU Press, 2018. http://dx.doi.org/10.18574/nyu/9781479807031.003.0007.
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This chapter makes the question of affective labor explicit as it works through Maureen Catbagan’s video series Crush (2010–2012), which features a woman in high heels crushing plastic toys. Catbagan’s decision to feature a white woman in this critique of domestic labor brings to light the pervasiveness of discourses of white feminine misery as read through Joan Riviere’s “Womanliness as Masquerade,” while also highlighting the object-centered nature of fetishism. Catbagan’s project asks viewers to read for race and sensuality in other modes because their Filipino identity is rendered invisible. This reorientation of representation produces brown jouissance in relation to mimesis and virality, thereby upending questions of value and commodification.
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Trinkaus, Erik, Alexandra P. Buzhilova, Maria B. Mednikova, and Maria V. Dobrovolskaya. "The Sunghir Human Skeletal Remains." In The People of Sunghir. Oxford University Press, 2014. http://dx.doi.org/10.1093/oso/9780199381050.003.0007.
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The Sunghir human remains originally consisted of the three associated skeletons from the two burials, Sunghir 1, 2, and 3, plus the remains of six other individuals. Sunghir 1 to 3 consist of largely complete skeletons that sustained the inevitable partial crushing, fragmentation, and bone disintegration that accompanies human remains buried in open air sites for 28,000 years. Sunghir 4 is the adult femur shaft that was ritually placed in the Sunghir 2 and 3 burial, next to the left shoulder of Sunghir 2 (chapter 3). Sunghir 5 is a partial adult cranium, found in the sediments above Grave 1. Sunghir 6 is a mature hemimandible, identified as human after excavation from among the faunal remains above Grave 2. There were also the unnumbered remains of the skeleton in Grave 2bis, which were not retained (see discussion in chapter 3). In addition to these human fossils, the remains of three additional individuals were originally found, numbered Sunghir 7 to 9. Sunghir 7 was found in the deposits between the two graves and consisted of a portion of a human femur, variously described as adolescent or from a young adult female. Sunghir 8 consisted of portions of a femur and a skull (a frontal bone, a probable parietal bone, and a temporal bone), found in 1969 in an additional clay pit. Sunghir 9 was a partial skeleton found in 1972 in an additional clay pit. None of the Sunghir 7 to 9 human remains can be currently located. The Sunghir 7 and 8 remains were briefly described by anthropologists and forensic scientists in Moscow, and the limited information on Sunghir 9 is based on reports by the Vladimir Ceramic Works workers. The available human remains from Sunghir therefore consist of the Sunghir 1 to 3 partial skeletons, the Sunghir 4 partial femur, and the Sunghir 5 and 6 cranium and mandible. These specimens are currently curated in the Laboratory of Anthropological Reconstruction of the Institute of Anthropology and Ethnology of the Russian Academy of Sciences.
Conference papers on the topic "Crushing work"
1
Mazur, Marcin. "METHOD OF DETERMINING THE BOND WORK INDEX IN VIBRATORY CRUSHING." In 17th International Multidisciplinary Scientific GeoConference SGEM2017. Stef92 Technology, 2017. http://dx.doi.org/10.5593/sgem2017/11/s04.115.
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2
Jenson, Sean, Muhammad Ali, and Khairul Alam. "Composite Core Cross Tube Crushing Analysis." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23839.
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Abstract Thin walled axial members are typically used in automobiles’ side and front chassis to improve crashworthiness of vehicles. Extensive work has been done in exploring energy absorbing characteristics of thin walled structural members under axial compressive loading. The present study is a continuation of the work presented earlier on evaluating the effects of inclusion of functionally graded cellular structures in thin walled members under axial compressive loading. A compact functionally graded composite cellular core was introduced inside a cross tube with side length and wall thickness of 25.4 mm and 3.048 mm, respectively. The parameters governing the energy absorbing characteristics such as deformation or collapsing modes, crushing/ reactive force, plateau stress level, and energy curves, were evaluated. The results showed that the inclusion of composite graded cellular structure increased the energy absorption capacity of the cross tube significantly. The composite graded structure underwent progressive stepwise, layer by layer, crushing mode and provided lateral stability to the cross tube thus delaying local tube wall collapse and promoting large localized folds on the tube’s periphery as compared to highly localized and compact deformation modes that were observed in the empty cross tube under axial compressive loading. The variation in deformation mode resulted in enhanced stiffness of the composite structure, and therefore, high energy absorption by the structure. This aspect has a potential to be exploited to improve the crashworthiness of automobile structures.
3
Ali, Muhammad, Eboreime Ohioma, and Khairul Alam. "Study of Energy Absorption Characteristics of Square Tube With Composite Cellular Core." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86916.
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Square tubes are primarily used in automotive structures to absorb energy in the event of an accident. The energy absorption capacity of these structural members depends on several parameters such as tube material, wall thickness, axial length, deformation modes, locking strain, crushing stress, etc. In this paper, the work presented is a continuation of research conducted on exploring the effects of the introduction of cellular core in tubular structures under axial compressive loading. Here, the crushing response of composite cellular core tube was numerically studied using ABAQUS/Explicit module. The energy absorbing characteristics such as deformation or collapsing modes, crushing/ reactive force, crushing stroke, and energy curves were discussed. The composite cellular core tube shows promise for improving the crashworthiness of automobiles.
4
Ali, M., J. Hoffman, J. Clark, and S. Takak. "Modeling of Impact Response of Composite Graded Structure." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64361.
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The work presented in this paper is a continuation of a study on exploring energy absorbing characteristics of a composite functionally graded structure found in a banana peel [1]. The impact behavior of peel structure under strain rates ranging from 4000 s−1 to 15000s−1 are studied. A modified mathematical model is presented, which calculates the initial dynamic crushing stresses of the structure at different impact velocities. The model outputs are compared with finite element simulations for the initial crushing stress, densification strain, global and local deformation modes, reactive force pulse, and total energy absorbed. A reasonable agreement is found between the proposed model and finite element simulations in determining the initial dynamic crushing stress and total energy absorbed by the structure.
5
Zarei Mahmoudabadi, M., M. Sadighi, and A. Eyvazian. "Theoretical and Experimental Crushing Analysis of Metal Square Honeycombs Under Quasi-Static Loading." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24739.
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Honeycomb cellular structures, due to their light weight and high energy absorbing, have been used extensively as energy absorbers or cushions to resist external loads. In this paper, the mean crushing stress and the wavelength of the folding mode, as two important parameters in the study of metal square honeycomb crushing under quasi-static loading have been investigated theoretically and experimentally. Firstly, by considering the true cylindrical curvature effects and the flow stress in the folding mode of the honeycomb material, the Wierzbicki’s model in the study of metal hexagonal honeycomb crushing under quasi-static loading is modified. This modification is performed by rewriting the internal energy terms and the external work in the energy method through the basic element folding by considering the true cylindrical curvature effects and the flow stress of the honeycomb material. Comparison of the results obtained by this modified model and Wierzbicki’s model with the experimental data shows better prediction by the model presented in this paper. Subsequently, this modified model has been extended to the study of metal square honeycombs crushing under quasi-static loading and the mean crushing stress and the wavelength of the folding mode of these structures have been predicted. This analytical model predicts the mean crushing stress of the metal square honeycomb as a function of both the geometrical parameters and its material, while the predicted wavelength of the folding mode is just a function of the geometrical parameters. Finally, the experimental tests have been performed to verify the preciseness of this theoretical model.
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Ali, M., J. Miller, and S. Takak. "Study of Impact Behavior of a Composite Graded Cellular Structure." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12377.
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The research study presented in this paper is a continuation of work done in analyzing the impact response of functionally graded cellular structure of a banana peel for energy absorbing applications. A composite graded cellular structure composed of three different materials is modeled in ABAQUS. The effects of composite sections on energy absorbing characteristics, e.g. deformation mode, crushing stress, stroke, acceleration pulse etc., are studied. An analytical model developed in previous study [1, 2] is used to simulate the quasi-static and dynamic crushing behavior of the composite structure. An agreement is found between finite element analysis and the analytical model.
7
Meyer, Janette J., Douglas E. Adams, and Eric R. Dittman. "Identification of Nonlinear Behavior in a Composite Structure With Core-Crushing Damage." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-34409.
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Many damage detection methods that are applied to composite structures rely on nonlinear features in the dynamic response of the structure to identify the presence of defects. Presently, there is not a complete understanding of the physical mechanisms that cause the nonlinear behavior of a damaged composite structure. Correlating specific types of damage mechanisms to the resulting nonlinear response characteristics they cause would allow the detection methods to classify the type of damage that is present in the structure. In this work, a drop tower was used to impact an aluminum honeycomb sandwich panel in order to induce core-crushing. The response of the damaged panel to sinusoidal excitations of various amplitudes at resonant, super-, and sub-harmonic frequencies was then measured. The amplitudes of these measured responses and the corresponding restoring force curves were then compared to a predictive model to identify the type of theoretical nonlinearity (i.e. quadratic or cubic stiffness, quadratic or cubic damping, etc.) that was present. The predictive model is based on a nonlinear, single degree-of-freedom system. Nonlinear features in the response of the system were identified for different types of stiffness and damping nonlinearities. The experimentally measured response was analyzed to see which of these features were present. Based on this analysis, the response of the panel of damage due to core-crushing indicated a quadratic spring-type stiffness.
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Ali, Muhammad, Khairul Alam, and Eboreime Ohioma. "Effects of Functionally Graded Cellular Core on Energy Absorption Response of Thin Walled Composite Axial Members." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66150.
Full textAbstract:
Thin walled axial members are typically used in vehicles’ side and front chassis to improve crashworthiness. Extensive work has been done in exploring energy absorbing characteristics of thin walled structural members under axial compressive loading. The present study is a continuation of the work presented earlier on evaluating the effects of presence of functionally graded cellular structures in thin walled members. A functionally graded aluminum cellular core in compact form was placed inside a steel square tube. The crushing behavior was modeled using ABAQUS/Explicit module. The variables affecting the energy absorbing characteristics, for example, deformation or collapsing modes, crushing/ reactive force, plateau stress level, and energy curves, were studied. An approximate 35% increase in the energy absorption capacity of steel tube was observed by adding aluminum graded cellular structure to the square tube. The aluminum graded structure crushed systematically in a layered manner and its presence as core supported the steel square tube side walls in transverse direction and postponed the local (tube) wall collapse. This resulted in composite tube undergoing larger localized folds as compared to highly compact localized folds, which appeared in the steel tube without any graded core. The variation in deformation mode resulted in increased stiffness of the composite structure, and therefore, high energy absorption by the structure. Further, a relatively constant crushing force was observed in the composite tube promoting lower impulse. This aspect has a potential to be exploited to improve the crashworthiness of automobile structures.
9
Ohioma, Eboreime, Muhammad Ali, and Khairul Alam. "Impact Performance of Cellular Core Hybrid Tubes Under Axial Compressive Loading." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70409.
Full textAbstract:
Thin wall structures are primarily deployed in automotive chassis to increase the energy absorption capacity of the automobiles in the event of an accident. Researchers have delved into developing lighter structures for improving automobiles’ fuel efficiency with a challenge of maintaining or preferably exceeding the energy absorption properties of the structure. In this study, the work presented is a continuation of research conducted on exploring the effects of the introduction of cellular core in tubular structures under axial compressive loading. The crushing response of cellular core hybrid tube was numerically studied using ABAQUS/Explicit module. The characteristics such as deformation or collapsing modes, crushing/ reactive force, locking strain, energy curves, and specific energy absorbed were studied. The cellular core hybrid tube shows significant potential for reducing the weight of automobile structure while giving positive indication towards enhancing the specific energy absorption capacity.
10
Jenson, Sean, Eboreime Ohioma, Muhammad Ali, and Khairul Alam. "Functionally Graded Cellular Core Cross Tube: Finite Element Study." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-10752.
Full textAbstract:
Abstract Thin wall structures are primarily deployed in automotive chassis to increase the energy absorption capacity of the automobiles in the event of an accident. Researchers have delved into developing lighter structures for improving automobiles’ fuel efficiency with a challenge of maintaining or preferably exceeding the energy absorption properties of the structure. In this study, the work presented is a continuation of research conducted on exploring the effects of the introduction of cellular core in tubular structures under axial compressive loading. The crushing response of cellular core cross tube was numerically studied using ABAQUS/Explicit module. The characteristics such as deformation or collapsing modes, crushing/ reactive force, locking strain, energy curves, and specific energy absorbed were studied. The cellular core cross tube shows significant potential for reducing the weight of automobile structure while giving positive indication towards enhancing the specific energy absorption capacity.